Apparatus for carbonizing briquettes



Sept. 26, 1933. E. wlLLsoN 1,927,968

APPARATUS FOR CARBONIZVING' BRIQUETTES original Filed Nov." l, 1928 imEJWLL WSZW@ Patend sept. 26, 1933 UNITED STATES APPARATUS FOR CARBONIZING BRIQUETTES Edwin L. Willson, Glenside, Pa., assignor to The LehighCoal and Navigation Company, Philadelphia, Pa., a corporation ofPennsylvania 1 claim. (C1. 2ozn This application is a division of myco-pending application Serial No. 316,596, filed November 1,

My invention relates to an apparatus for carbonizing briquettes.

Heretofore, considerable difculty and much annoyance has beenexperienced with the usual solid-hearth plates used in connection. withcarbonizing processes. Such plates deteriorate very rapidly in serviceand, by reason of their ,relatively large expense, greatly increase thecost of the carbonizing operation. Moreover, when the hearth isreplaced, the furnace as a whole must be shut down, with the result'thata further loss occurs. One object of my invention, therefore, is toprovide a hearth which overcomes the abovenoted dimculties-my inventioncontemplating the use of an automatically-renewable porous bed of hotmaterial as a hearth. A bed of this character may be formed of minerefuse having a very low market value.

Other objects and applications of my invention, as well as details ofconstruction and operay tion, whereby my invention may be practiced,will be apparent more fully hereinafter, when taken in connection withthe accompanying drawing, wherein The single gure of the drawing is aView partially in section and partially in side elevation of a structureembodying my invention.

Referringv to the drawing, a chamber 1 of a furnace 2 is provided with apassage 3 which extends therefrom through an upper, horizontal side wall4 to an exteriorly-positioned hopper 5 containing the material to betreated. This material, in one installation, took the form ofbriquettes, which were first pressed into shape by means not shown andthen deposited in the hopv per 5.

In accordance with my invention, the briquette passage 3 terminates inan open end 6 which is positioned just above a fuel bed 7 constitutingan automatically removable hearth. The fuel bed '1 is supported on amovable grate surface 8 af,- forded by an upper side 9 of a travelinggrate stoker 10. A front end 11 of the stoker 10 extends through anopening` 12 in the front portion of the furnace. bonizing chamber 1 isprovided with a fuel-passage opening 14, whereby a carbonaceous fuel 15such as coke breeze or small sizeof anthracite, may pass. from anexteriorly-positioned hopper 16 through the opening 14 onto the movablegrate surface 8, as shown in the single figure of the A front wall 13 ofthe car".v

drawing. A door 17 serves to control the rate of fuel supply.

The green coal 15, upon entering the chamber 1, is preferably heated tothe point of incandescence, the air necessary lto support combustion atthis point being at least partly supplied by means of air passages 18,18 positioned directly under the grate surface. These passages may besupplied with air through ducts 19 which are connected to the passages18, 18 by 65 tuyres 21. Additional air passages 22, 22 and 23, 23 arepositioned under the grate surface 8 and supplied with air through ducts24 and 25, respectively, so that the fuel bed '7 may assume the generalform shown in the drawing, wherein it is noted that an intermediateportion 26 is .formed of incandescent coal, while a rear end portion 27is formed of hot ashes. These ashes are dropped from an inner end 28 ofthe stoker 9 into an ash-pocket 29 which is formed be- 75 tween thestoker 9 and a rear wall 31 of the chamber l.

As shown on the drawing, the inner open end 6 of the passage 3 is spacedfrom the front wall portion 13, so that the briquettes are deposited onthe front portion of the incandescent part of the fuel bed '7. Theforward movement of the stoker 10 causes the supermposing of a layer 32of briquettes on the fuel bed 7. While the fuel bed'l, and thesuperimposed layer 32 of briquettes are 85 moving rearwardly'through thechamber l, the briquettes are heated as a result of direct contact withthe fuel bed 7 and the air which passes` upwardly through the porousfuel bed 7 and the layer of briquettes 32. As a result, carbonization ofthe briquettes occurs and certain of the gases in the briquettes 32 aredriven off, mingling with the hot gases passing from the fuel bed 7.

In order that the gases from the heated briquettes may be caused toburn, and thus afford an additionai supply of heat to that furnished bythe fuel bed 7, a plurality of air openings 33 may be formed in thecarbonizing chamber 1 immediately adjacent to an upper rear wall portion34 thereof. The burning of the fixed carbon in' l the layer ofbriquettes is prevented by the control of the amount of air supplied tothe 'underside of the fuel bed '7, and to the air openings 33, as wellas the control of the rate of operation of the stoker 10. In oneinstallation the rate of l stoker operated was such that a coking periodof only thirteen minutes was required. The hot gases formed in thecarbonizing chamber 1 may be passed upwardly therefrom through a passage35 vto a boiler system 36, which serves as an l 'energy-translatingmeans, converting the heat of the gases to steam.-

In operation, assuming the presence of the porous fuel bed 7 on thegrate surface 8, as shown in the drawing, movement of 'the stoker 10results in the' formation of the layer 32 of briquettes. Thesebriquettes, upon being deposited on the fuel bed '7, are heated byconduction due to direct contact with the fuel bed 7 by convection dueto the air passing through the stoker110 and the bed 7 thereon, and byradiation from the heat incident to the burning of the gases in thechamber 1. As a result, the briquettes are heated and evolve a gas whichmingles with that passing through the fuel bed 7 and burns in the upperportions of the carbonizing chamber 1. When the briquette finallyreaches the rear end `28 of the Stoker 9, carbonization to the desiredextent has occurred and the briquettes, as Well as the ashes, are passedinto the pocket 29 which is provided with a quenching tank 37 in thebottom thereof. The fuel bed 7'thus serves as an .automatic renewablehearth which is formed of material having an exceedingly low marketvalue. Experience has shown that such type of hearth permits an increasein the thickness of the layer of briquettes without sacrificing theuniformity of carboniZatiOn, as compared with the solid type of hearthvheretofore used. Should it be desirable to interrupt the briquettingoperation, the energy developed by the boiler 36 may be maintainedsubstantially constant by merelyincreasing the amount of refuse fuelfeed to the Stoker 9 from the hopper 16.

While I have shown only one form of embodiment of my invention, for thepurpose of describing the same and illustrating its principles ofconstruction and operation, it is apparent that various changes andmodications may be made therein, without departing from the spirit of myinvention. For example, the porous bed of hot material constituting thehearth may be formed of a non-carbonaceous material, as, for example,sand, and satisfactory operation still obtained. I desire, therefore,that only such limitations shall be imposed thereon, as are indicated inthe appended claims or as are demanded by the prior art.

I claim: l

In carbonizing apparatus, the combination with a carbonizing chamber, ofa grate, means located externally of the chamber for feeding fuel tosaid grate, means within the chamber for supplying material to becarbonized to said grate, means for passing a current of air upwardlythrough said superposed layers to raise combustable gases fromsaidlayers and to support combustion of said gases, and means forinjecting supplementary air into said chamber above the uppermost ofsaid layers for mixing With said gases to stimulate combustion thereofabove the layer of material being carbonized. I

EDWIN L. WILLSON.

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